Lamtec BT300 BurnerTronic, Быстрая справка

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6 Leakage Test for Main Gas Valves
6.2 Leakage Test Process Flow
The valve leakage test checks if the main gas valves are sealed. For this purpose the gas
pressure of the supply is analysed.
As valve leakage test section (space between the two main valves) burns empty whenever the
burner is switched off, this part is usually pressureless at start-up (gas pressure > min = 0).
This is checked by BT300. At this point, main gas 1 opens briefly and gas flows into test sec-
tion (gas pressure > min switches from 0 to 1). While main gas 1 valve is open gas pressure
must apply.Otherwise BT300. detects gas deficiency. Gas pressure must remain at least con-
stant during valve leakage test period (2 s + P 311). The valve leakage test is considered com-
plete then.
If leakage test section is not empty at start-up (e.g. resulting from a previous fault shut down),
main gas valve 2 opens first. The leakage test line is then purged (depending on the plant,
either in the combustion chamber or through the roof). During leakage test period section is
checked whether it remains pressureless or not. Apart from that the process is the same as
described above.
The leakage test takes place prior to ignition.
The pressure monitor for the leakage test line must be connected to the ’Gas pressure > min’
input on plug X05. It also monitors the minimum pressure during operation. If a different min-
imum pressure should be monitored during operation, the pressure monitor must be inserted
into the safety interlock chain gas or into the controller loop (burner ON).